Concise Update on Genomics of COVID-19: Approach to Its latest Mutations, Escalated Contagiousness, and Vaccine Resistance.

The novel coronavirus disease 2019 (COVID-19) that started to invade the world from the Chinese fish market, causes an acute respiratory distress syndrome. COVID-19 is a dreadful infectious disease that surfaced only less than 8 months ago and caused the deadly COVID-19 pandemic. In this new species with a positive, single-strand RNA genome and a huge size, from the proteomics point view, there are no changes in sequences of amino acids in NSP7, 13, matrix, or envelope or other proteins including 8b and p6 and excluding NSP2 and NSP3. P6 is a multifunctional golgi-endoplasmic reticulum membrane-associated protein. This complex has a key duty to increase the replication rate of the virus and also causes intrinsic immune system responses by suppressing the signal transducer and activator of transcription factor 1 (STAT 1) translocated to the nucleus. Palmitoylated proteins elevate hydrophobicity which helps in membrane connection. Inside the N-linked glycosylation, moieties oligosaccharide is adhering to Asn-X-Ser/Thr canonical sequence. This helps for exact enfolding and carrying viral proteins by industriously using host's chaperon proteins including calreticulin and calnexin. 2B proteins encourage the internalization of major histocompatibility complex, class-I (MHC-I) protein and meanwhile inhibit their transfer to the surface of the cell as a recognition side. The deubiquitination of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has precise modification apparatus in the posttranslational stage. In this article, we outlined the recent and up-to-date data on genomic and molecular structures, epidemiology, vaccine development, and, last but not least, the clinical features, diagnostics, and treatment of the novel coronavirus.

Identification of Quinolone and Colistin Resistance Genes in Escherichia Coli Strains Isolated from Mucosal Samples of Patients with Colorectal Cancer and Healthy Subjects.

INTRODUCTION: Antibiotic resistance and extensive use of antibiotics are amongst the major causes of failure in antibiotic treatment. The purpose of this study was to investigate antibiotic resistance patterns and to identify resistance genes of quinolones and colistin in Escherichia coli. There are a very few patents on E. coli isolated from colorectal cancer. So, this study demonstrates that some bacteria resistant to ciprofloxacin have not resistance genes.Moreover, new patterns for E. coli are presented for isolates of patients with colorectal cancer. MATERIALS AND METHODS: Of the three healthy people, inflammatory bowel diseases (IBD) patients and colorectal cancer patients, 40 E. coli strains isolated after confirmation by biochemical and molecular methods. The susceptibility of isolates to antibiotics was investigated using disk diffusion test. After deoxyribonucleic acid (DNA) extraction, polymerase chain reaction (PCR) was used to identify genes encoding resistance to ciprofloxacin (qnr A, qnr B) and colistin (mcr-1). RESULTS: The results showed that E. coli isolates from colorectal cancer patients had the highest resistance to piperacillin (67.5%), ceftazidime (47.5%), and cefepime (42.5%). Also, E. coli strains isolated from IBD patients showed resistance to antibiotic ceftazidime 13%. More than 95% of E. coli strains isolated from healthy people were susceptible to antibiotics. Based on the results, 18 (15%) E. coli strains showed resistance to ciprofloxacin. The qnr A gene was detected in 61.11% isolates; however, qnr B was detected in 9 (50%) isolates. Isolates resistant to colistin were not observed. CONCLUSION: These findings indicate increased resistance of E. coli to ciprofloxacin in comparison with prior studies. Further research in this field will increase our knowledge and more effective exposure to the antibiotic resistance of the pathogenic microorganisms.

Effect of Green Tea Varnish on Depth of Root Caries.

AIM: Root caries is a common, debilitating condition particularly in the elderly population, which can lead to tooth loss. Evidence shows that green tea has cariostatic effects. Considering the gap of information on green tea varnish, this study aimed to assess the efficacy of green tea varnish in the prevention of root caries. MATERIALS AND METHODS: This in vitro experimental study was performed on 42 sound premolars. Two layers of acid-resistant nail varnish were applied on root surfaces except for a window of 1 × 4 mm. The teeth were randomly divided into three groups (n = 14). Group I (control) received no intervention. Group II received green tea varnish applied on the roots every 48 hours for 21 days. Group III received green tea varnish every 24 hours for 21 days. Sections of 40 µ thickness were prepared from the center of the window, and the depth of carious lesion was measured in three points with 500 µ distance from each other using polarized light microscope. Data were analyzed using Statistical Package for the Social Sciences (SPSS) version 16 and non-parametric Kruskal-Wallis and Mann-Whitney U tests (α = 0.05). RESULTS: The mean (and standard deviation) depth of carious lesion was 54.30 ± 28.64 (µm), 0, and 0 in groups I, II, and III respectively. Control group showed the highest depth of caries. Groups II and III were not significantly different in this respect, but significant differences were noted in depth of caries between groups I and II and also groups I and III (p < 0.001). CONCLUSION: Based on the results, the green tea varnish may possess anticariogenic effects on root caries when applied every 24 or 48 hours over a 21-day period. Application of green tea varnish every 24 or 48 hours for 21 days may prevent root caries. CLINICAL SIGNIFICANCE: Application of green tea varnish can prevent root caries.